1. Field of the Invention
This invention relates to semiconductor devices. In particular the invention relates to semiconductor devices incorporating a superlattice.
2. Description of the Prior Art
Superlattices comprise a periodic structure consisting of alternating ultra-thin layers of two different semiconductor materials, the semiconductor materials being chosen such that there is a misalignment of energy band edges between each pair of adjacent layers, with the layers of one of the materials constituting potential barriers to charge carriers passing through the superlattice.
The original work on these structures was performed by L. Esaki and L.L. Chang, and is described in Physical Review Letters, Volume 33, pages 495 to 498. A recent review article on superlattices is given in Proceedings of the 17th International Conference on Physics of semiconductors, edited by Chadi and Harrison, Published by Springer Verlag in 1985, pages 473 to 483.